<?php
class GoogleRank {
	function zeroFill($a, $b){ 
	 $z = hexdec(80000000);
	  if ($z & $a){ 
	   $a = ($a>>1); 
	   $a &= (~$z); 
	   $a |= 0x40000000; 
	   $a = ($a>>($b-1)); 
	  }else{ 
	   $a = ($a>>$b); 
	  } 
	 return $a; 
	} 
 
 function mix($a,$b,$c) { 
   $a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,13));
   $b -= $c; $b -= $a; $b ^= ($a<<8);
   $c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,13));
   $a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,12));
   $b -= $c; $b -= $a; $b ^= ($a<<16);
   $c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,5));
   $a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,3));
   $b -= $c; $b -= $a; $b ^= ($a<<10);
   $c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,15));
   return array($a,$b,$c);
 } 
 
 function GoogleCH($url) { 
  $length = sizeof($url); 
   
  $a = $b = 0x9E3779B9;
  $c = 0xE6359A60;
  $k = 0;
  $len = $length;
  while($len >= 12) { 
   $a += ($url[$k+0] +($url[$k+1]<<8) +($url[$k+2]<<16) +($url[$k+3]<<24));
   $b += ($url[$k+4] +($url[$k+5]<<8) +($url[$k+6]<<16) +($url[$k+7]<<24));
   $c += ($url[$k+8] +($url[$k+9]<<8) +($url[$k+10]<<16)+($url[$k+11]<<24));
   $mix = $this->mix($a,$b,$c);
   list($a, $b, $c) = $mix;
   $k += 12;
   $len -= 12; 
  }
  $c += $length;
  switch($len){ 
   case 11: $c+=($url[$k+10]<<24);
   case 10: $c+=($url[$k+9]<<16);
   case 9 : $c+=($url[$k+8]<<8);
   /* the first byte of c is reserved for the length */
   case 8 : $b+=($url[$k+7]<<24);
   case 7 : $b+=($url[$k+6]<<16);
   case 6 : $b+=($url[$k+5]<<8);
   case 5 : $b+=($url[$k+4]);
   case 4 : $a+=($url[$k+3]<<24);
   case 3 : $a+=($url[$k+2]<<16);
   case 2 : $a+=($url[$k+1]<<8);
   case 1 : $a+=($url[$k+0]); 
  } 
  $mix = $this->mix($a,$b,$c); 
 	/* report the result */ 
 	return $mix[2]; 
 } 
 
 //converts a string into an array of integers containing the numeric value of the char 
	function strord($string) { 
		for($i=0;$i<strlen($string);$i++) { 
			$result[$i] = ord($string{$i}); 
		}
		return $result; 
	}
 
 function rank($url){
  $ch = "6".$this->GoogleCH($this->strord("info:" . $url)); 
  $pagerank = 0;
  
  $page = 'http://www.google.com/search?client=navclient-auto&ch=' . $ch .  '&features=Rank&q=info:' . $url;
  $page = file_get_contents($page);
	if (preg_match('|Rank_....([0-9]+)|', $page, $matches)) {
		$pagerank = $matches[1];
	}
  
  return $pagerank;
 }
}